A recent experiment carried out at Michigan State University looked at the effects of two ad libitum feeding and watering methods on the performance of lactating sows.  The first was a self-fed wet/dry feeder and the second a hand-fed feed system with a separate water source.  In the wet/dry feeder, feed and water were dropped into a trough, with the sow deciding how much feed and water to release. Because feed and water became mixed together in the trough, the sow also determined the wetness of the feed consumed.  In the hand-fed system, sows were given dry feed twice daily in a J-shaped feeder that was independent of the sow’s water source.   Total feed disappearance per sow during a 20-day lactation was greater with the wet/dry system than with the hand-fed system (120 vs. 110 kg, respectively). The sows fed with the wet/dry feeder also had greater body weight gains during lactation than hand-fed sows (6.2 vs. 1.85 kg, respectively). Backfat depth change during lactation did not differ between treatments, nor did the percentage of sows displaying estrus by day 11 post-weaning.  Piglet weaning weight was greater (6.63kg) with the wet/dry system than with the hand-fed system (6.12kg).  The sows’ average daily water intake and total feed wastage during lactation did not differ between treatments. However, sows using the wet/dry feeders wasted less water than those with the hand-fed system (15 vs. 232 L, respectively).  The authors noted that the difference in waste water volume would result in a significant variation in costs associated with manure storage and distribution.  In conclusion, use of a sow-operated wet/dry feed-water system in lactation, which provides sows choices of when to eat, how much to eat, and if dry feed should be mixed with water during consumption, enhances sow appetite, improves litter growth performance, and wastes less water than a hand-fed feed-water system.

WHJ comment:  With the vastly increased nutritional demands on todays sows, any means of improving the amount of feed consumed during lactation will be beneficial because there is a direct relationship between body weight loss during the suckling period and subsequent litter size.  The 10kg difference in total lactation feed intake is considerable, even though it did not result in a difference in backfat at weaning or wean to estrus interval.  However, the biggest benefit was in weaning weight, which increased by over 0.5 kg. Bearing in mind the effect of weaning weight on subsequent growth rate, this is an extremely valuable improvement. The difference in water wastage between a drinker over the trough and a regular crate-mounted nipple is quite staggering and is another reason for considering a wet/dry type feeder. Overall, this trial indicates the big impact of lactation feed intake on sow performance and suggests that producers should be paying more attention to this crucial area.

Reference:  J. J. Peng, S. A. Somes and D. W. Rozeboom – Effect of system of feeding and watering on performance of lactating sows, J. Anim Sci. 2007. 85:853-860. doi:10.2527/jas.2006-474